A simple calculation method for estimating the shielding effectiveness of a conducting spherical cell

In this paper a simple calculation method for estimating the shielding effe ctiveness of a conducting spherical cell is proposed. The spherical cell ha s a small size compared with the wavelength. The shielding effectiveness of a conducting spherical cell with a small antenna set in it is analyzed by approximated equation using the F matrix of the distribution circuit theore m. The calculation results using the proposed approximated equation coincid e with an error of a few decibels compared with the results of the rigorous solution of the spherical wave equation. Good agreement is also obtained w ith the experimental results. The proposed calculation method without Besse l and Hankel functions included in the rigorous solution is very easy to es timate the shielding effectiveness. (C) 2000 Scripta Technica, Electron Com m Jpn Pt 1, 84(1): 84-90, 2001.